Roku is once again talking up plans to open its Netflix-only set-top box to other online video providers. Talking at the Streaming Media West conference, Roku CEO Anthony Wood was quoted as saying:

“We’re going to release the software developer kit [SDK], so anyone can publish any channel, and users can access web content on their TVs.”

Of course, just releasing an official SDK won’t lead to the Internet TV set-top box nirvana that we, and Roku, are seeking. For that to happen, Netflix’s competitors will need to be persuaded that it’s worth their while to actually build something using Roku’s SDK, otherwise poular services such as Hulu, BBC iPlayer or YouTube, for example, may never make it onto the set-top box.

As Dave Zatz advises: Roku needs to “continue working the phones” in order to build the kind of partnerships that will lead to more quality content. Because its content that will ultimately lead to more hardware sales, which is of course where Roku makes its money. “There’s a much larger audience of potential Hulu and YouTube viewers than there are Netflix subscribers”, notes Zatz.

One potential sticking point: Earlier this year Netflix made a small investment in Roku, which could make things awkward as Roku attempts to woo competing content partners.

It was only yesterday that our friend Dan Rayburn over at Streaming Media was talking down the impact that Internet-delivered video was making in the living room. Or to quote Rayburn himself, his guest post for GigaOm was intended to “set expectations properly”, based on official figures and various estimates, which suggest that consumer facing set-top boxes from the likes of TiVo, Sony, Microsoft, Apple, Roku and Vudu that are capable of delivering online video, have sold a lot less than what most people think.

Today, however, Rayburn admits he got one figure wrong. Based on a new source, Rayburn says that rather than selling 10,000 units, the Netflix player by Roku has sold closer to 100,000.

While it surprised me the number was that high, it does seem possible, as that would equal about 1% of Netflix’s 8.2 million customers. Considering the price point ($99) and the fact that the product’s marketing is very focused, to a targeted audience, Roku’s penetration rate would be higher than the average product that has only been on the market for eight weeks. Plus, once you have the Roku box, the content is free.

Rayburn goes on to suggest that it won’t be long before the Roku box outsells the AppleTV (we don’t disagree), especially with the promise that the Roku player will soon support more than just Netflix. “This little device has some real potential to make a real impact in the market”, he says.